204 
VETERIN ARIUS. 
Many pulmonary diseases of the horse are characterized by 
the presence of circumscribed productions of the most variable 
character and form, and veterinarians frequently designate every 
variety of nodulus met with in the lungs as tubercle. Even in the 
present day we often find glanders noduli mistaken for genuine 
tubercles. Even though the products in tuberculosis resemble 
those of glanders, still, from an etiological point of view, they 
vary essentially from one another. It must also be borne in mind 
that genuine tuberculosis is an exceedingly rare disease in the 
horse, and that the fresh tubercle is pearly and transparent, the 
older opaque and whitish, while the nodulus of glanders is, when 
fresh, gray, but later on yellow, and finally bears a strong resem¬ 
blance to small abscesses. A glanders nodulus resembles tubercle 
in that they frequently form nests or conglomerate masses, and 
break down, especially when superficially situated, as in a mucosa. 
It is incorrect to compare the ulceration of a glanders nodulus 
to the bursting of an abscess. When an abscess comes to develop¬ 
ment, the tissues are destroyed, in place of which a cavity is 
formed, filled with pus, which finally bursts, leaving a distinct in¬ 
terruption in the continuity of the tissues involved; on the con¬ 
trary, a glanders nodulus undergoes a gradual process of ulcer¬ 
ative destruction, the material which escapes being the detritus or 
remnants of destroyed tissues. This , softening or ulcerative de¬ 
generation does not at once complicate the entire nodulus; the 
base and circumference of the neoplasm are the seat of neoplastic 
granulations, presenting a lardaceous appearance. Such an ulcer¬ 
ated nodulus gradually cleans itself of its necrobiotic elements, 
leaving nothing but a superficial ulceration having a peculiar form, 
which has given to it the name of “ lenticular ulcer.” 
These lenticular ulcers have frequently been described as ero¬ 
sions, which is entirely wrong. An erosion is the removal of the 
epithelial covering from underlying tissues. In lenticular ulcera¬ 
tions, not only the epithelium, but a portion of the tissue under 
it, undergo necrobiotic destruction. 
The development of glanderous nodules, and the progressive 
process of ulcerative destruction which it undergoes, can be ob¬ 
served best in the nasal mucosa. In a short time, in the circum- 
